Indicator for elevators



(No Model.)

" E. MARSHALL.

INDICATOR FOR ELEVATOR-S.

No.v349, 729. Patented Sept. 28, 1886.

UNITED STATES PATENT OFF E.

ELIAS MARSHALL, OF BOSTON, MASSACHUSETTS.

I NDICATOR FOR ELEVATORS.

SPECIFICATION forming part of Letters Patent No. 349,-729, dated September 28, 1886.

Application filed February 8, 1886. Serial No. 191,262.

. same to be described in the following specifi cation and represented in the accompanying drawings, of which Figure 1 is a view, partly in vertical section, of an elevator and parts adjacent thereto provided with my invention. Fig. 2 is a vertical section of the aircompressor, and Fig. 3 is a similar section of one of the storygages hereinafter described.

In such drawings, A denotes one wall of an elevator shaft or well, and B, O, and D the floors of the stories next thereto, the lift or elevator being represented at E as at its highest altitude. From the said elevator a rope, a, winds about and is secured to a drum, 6, upon whose shaft is a gear, a, that engages with a train of gears, d, e, f, g, and g, the last of which meshes into a toothed rack, h, extending down from the air-compressor F, arranged as represented. The said air compressor consists of two straight tubular vessels, i and k, the lower of which, closed at the bottomland open at the top, receives within it the upper one, which, closed at top and open at bottom, is fitted within the said lower vessel, so that the latter may slide air-tight thereupon. The vessel 13 is to have within it a charge, 1, of mercury or some other proper fluid, and isto be movable vertically upon the vessel k, which is to be supposed to be stationary or fixed in position. A pipe, m, opening out'of the vessel k, at its top communicates with an ordinary pressure-gage, G, there being to the said pipe a stop-cock, n, to cut off the passage of air into the gage as occasion may require. Furthermore, there opens out of the pipem another pipe, 0, provided at its upper part with a stop-cock, p.

The said pipe 0 descends and communicates by a series of branch pipes, q, with several mercurial or spirit gages, H, one of whichis in each story of the building. Each of the said gages H is to have on its glass column 1', or aside thereof, a scale, s, of a suitable kind (No model.)

to indicate different altitudes of the elevator, or when it may be at any one of the stories of the building. This scale is shown in Fig. 3 by the numerals 1, 2, 3, 4., and 5 opposite to marks or dots made on the outer tube. Each gage H has a closed reservoir, 15, to contain the mercury or fluid that by the pressure of the air in the reservoiris to be forced therefrom through a tube, a, into the internal glass tube, o, of the gage.

While the elevator or lift may be descending, the rack it will be moving downward, and

as a consequence the portion i of the air-compressor will likewise bein movement downward, and will carry with itthe liquid charge thereof, and thus relieve the pressure on the air within the pipes and allow the liquid to,

fall simultaneously in all the pressure-gages, and in so doing will cause them to indicate the altitude of the elevator E, or whatever story of the building it may be at during its descent. In a rise of the elevator the vessel 13 will be elevated, so as to create in the vessel It a compression of the air thereof and in the pipes leading from it to the gages. Such gages will then be caused to indicate the altitude of the elevator or the floor that from time to time it may reach, so that a person in any story of the building, by looking at the gage therein, can determine the position or height of the elevator.

For each of the columnar gages H an ordinary pressure-gage provided with a dial and an index pointer or hand to revolve thereon may be substituted, such dial having on it deapplied to such car and the machine for operating it.

I am aware of the elevator-indicator described and represented in the United States car a tank containing water, and from such tank a flexile pipe descends,'all of which has to be lifted by the car in ascending. In my indicator the air-compressor is stationary and separate from and not movable with the car, and, besides, I have no fiexile, pipe to rise or be drawn up with the car, nor any pipe in the form of a loop to connect with such flexile pipe.

I claim The combination of the air-compressor and its operative mechanism, substantially as described, arranged out of and above the lift or elevator, and stationary. relatively thereto, as explained, with such lift or elevator, the series of pressure-gages arranged in the different stories of a building, and connected with such IO air-compressor by one or more pipes, all being essentially and. to operate as and for the purpose set forth.

ELIAS MARSHALL. Witnesses:

R. H. EDDY, R. B. TORREY. 

